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Several former NFL players, including retired stars Jamal Lewis and Dorsey Levens, state in a federal lawsuit against the NFL that brain injuries have hampered their daily lives just several years after retirement, according to ESPN.com.

According to the lawsuit, the retired players claim that the NFL knew in the 1920’s about the potential for concussions in the league, and the long-term harm it could have on its players.

"The NFL has done everything in its power to hide the issue and mislead players concerning the risks associated with concussions," the players argue in the lawsuit.

The NFL responded to the lawsuit in a statement:

"Any allegation that the NFL intentionally sought to mislead players has no merit," the league said in a statement to The Associated Press on Thursday. "It stands in contrast to the league's actions to better protect players and advance the science and medical understanding of the management and treatment of concussions."